荧光/MRI双模态靶向成像诊疗试剂的制备

Synthesis of Fluorescence/MRI Dual Targeted Imaging Theranostics Reagent

在聚乙二醇二胺(NH_(2)-PEG-NH_(2))修饰的石墨烯量子点(GODs)表面以酰胺键偶联二乙基三胺五乙酸(DTPA)分子,之后将Gd^(3+)离子与其进行配合,得到了GODs-Gd(DTPA)复合纳米粒子,然后再通过酰胺键在GODs-Gd(DTPA)的表面修饰叶酸(FA)靶分子,最后进一步将阿霉素(DOX)通过π-π堆垛吸附在造影剂的表面,制备了FA/GODs-Gd(DTPA)/DOX荧光/MRI双模态靶向肺癌细胞成像诊疗试剂,通过透射电子显微镜、紫外可见吸收光谱、荧光光谱和激光共聚焦扫描显微镜等手段表征了其形貌、发光性能和靶向成像性能。MRI、激光共聚焦扫描显微镜和MTT等结果表明,相对于正常的HLF细胞,所制备的FA/GODs-Gd(DTPA)/DOX纳米粒子能够靶向检测FA受体高表达的肺癌H460细胞,并具有明显的抗肿瘤活性。

Poly(ethylene glycol diamine)(NH_(2)-PEG-NH_(2))modified graphene quantum dots(GODs)were conjugated with diethylenetriaminepentaacetic acid(DTPA)via an amide bond.Then the product further coordinated with Gd^(3+)ions,followed by the subsequent linkage of folic acid(FA)to form FA/GODs-Gd(DTPA).Next,an anticancer drug,doxorubicin(DOX),was loaded on the surface of FA/GODs-Gd(DTPA)to obtain the final fluorescence/MRI dual targeted imaging diagnostic reagents(FA/GODs-Gd(DTPA)/DOX)for lung cancer cells.The sample was character-ized by transmission electron microscopy,UV-Vis absorption spectroscopy,fluorescence spectroscopy,laser confo-cal microscopy,and so on.Compared with normal HLF cells,the results of MRI,confocal laser scanning microscopy and MTT showed that the prepared FA/GODs-Gd(DTPA)/DOX could be targeted to detect lung cancer H460 cells,in which folate receptor was highly expressed,and also displayed significant anti-tumor activity.